<u>Answer</u>: No, we do not have sufficient evidence to conclude that the mean call duration, µ, is different from the 2010 mean of 9.4 minutes.
Step-by-step explanation:
As per given , we have
, since 
is two-tailed so , the test is a two tail test.
Since population standard deviation is unknown, so we use t-test.
Critical value (two-tailed) for significance level of 0.01= 
For n =50 , 
and s= 4.8
Test statistic : 
Since test statistic value (-1.18) lies in critical interval (-2.609228, 2.609228), it means the null hypothesis is failed to reject.
We do not have sufficient evidence to conclude that the mean call duration, µ, is different from the 2010 mean of 9.4 minutes.
Answer:
-1.9
Step-by-step explanation:
I rounded it to the tenth
Answer:
Gregoire is correct; the diameter is a chord that passes through the center of the sphere.
Step-by-step explanation:
A sphere is a geometrical shape formed from a circle. Some of its parts are: diameter, center, radius circumference, etc.
The center of a sphere is a point at its middle. The diameter is a straight line, e.g a chord, that is drawn from one point on the circumference of a sphere to another point and passes through its center. While radius is a line that is from the center of the sphere to a point on its circumference.
A diameter is twice of a radius, so that:
Radius = 
⇒ Diameter = 2 × Radius
Therefore with respect to the question, Gregoire is correct because a diameter is a chord that passes through the center of the sphere.
